Subway currently has 87 outlets in Northern Ireland
More than 500 new jobs are to be created by two companies.
A financial services company is to create 110 new jobs in Newry, County Down, as part of an expansion package.
First Derivatives, which provides consultancy and software services, has been in the city since 1996 and already employs more than 100 people.
US sandwich chain Subway is to create up to 400 jobs. There are 87 stores in NI and the company plans to open 40 new franchises by the end of 2010.
Seventeen new outlets opened in Northern Ireland last year.
Franchisee Andrew Johnston, who runs 13 stores, said: "It is a really positive sign that the number of new store openings is continuing to grow across Northern Ireland, especially as businesses face tough trading conditions."
First Derivatives Chief Executive Officer Brian Conlon said they were "a recognised brand in the financial services sector".
"Our niche products and services continue to enjoy strong demand," he said.
"Critical to this success has been innovation across all areas of the business, as well as significant investment in training and development."
The jobs include consultancy positions and 10 new managerial posts to facilitate further global growth for the firm.
Invest NI has offered more than £3m to support the project, which includes an element of staff skills development.
Economy Minister Arlene Foster said the firm was one of Northern Ireland's "most innovative and successful export companies."
"This is extremely positive news from a home grown company at a time where many local firms are feeling the effects of the global economic downturn," she said.
The company is based in Newry and has ongoing assignments in many of the world's leading financial centres such as London, New York, Philadelphia, Toronto, Stockholm, Frankfurt, Dublin, Hong Kong and Singapore.